The Nimrod Review - Official Documents

The Nimrod Review
(10) ‘Normalisation of deviance’
17.27
17.28
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Shuttle managers had become conditioned over time not to regard foam loss or debris as a safety issue. A
foam strike (FOD) 24 was considered a “maintenance and turnaround concern rather than a safety issue”. 25 Over
22 years, foam strikes were normalised to the point where they were simply regarded as a maintenance issue
which did not threaten a mission’s success. Examination of photograph records confirmed that there had been
some foam loss on 82% of previously photographed Shuttle take-offs. 26 The acceptance of events that are not
supposed to happen is pithily described by sociologist Diane Vaughan as the “normalisation of deviance”. 27
Flying with foam losses became viewed as “normal and acceptable”. The parallels with Challenger, where flights
continued despite known ‘O’-ring problems, were said to be striking. 28
Fuel leaks on large ‘legacy’ aircraft in the MOD were regarded as an inevitable fact of life (and to some extent
still are).
(11) ‘Success-engendered optimism’
17.29 NASA suffered from “success-engendered safety optimism”, i.e. a belief that because a risk had been successfully
avoided in the past it was unlikely to transpire in the future. The SIAT warned that NASA “must rigorously guard
against the tendency to accept risk solely because of prior success”.
17.30 The good track record of the Nimrod led to the prevailing “high level of confidence” in the safety of the fleet.
The view that the Nimrod was ‘safe anyway’ and ‘acceptably safe to operate’ blinded many of those involved
in the Nimrod Safety Case.
(12) ‘The few, the tired’
17.31 One experienced observer of the space program described the shuttle workforce as “The few, the tired” and
suggested that “...a decade of downsizing and budget tightening has left NASA exploring the universe with a
less experienced staff and older equipment”. 29
17.32 This is increasingly true of the RAF and parts of the MOD (see Chapter 19 and the 2008 Capability Health
Check).
Further citations from the CAIB Report
17.33
The following citations from the CAIB Report are strongly reminiscent of the organisational causes of the loss of
Nimrod XV230 and the problems with the MOD safety and airworthiness culture found by the Nimrod Review:
17.33.1
“NASA’s safety culture has become reactive, complacent, and dominated by unjustified optimism.
Over time, slowly and unintentionally independent checks and balances intended to increase safety
have become eroded in favour of detailed processes that produce massive amounts of data and
unwarranted consensus, but little effective communication. Organisations that successfully deal
with high risk technologies create and sustain a disciplined safety system capable of identifying,
analysing and controlling hazards through a technology’s life cycle.” 30
24 Foreign Object Damage (FOD).
25 CAIB Report, page 126.
26 Photographs images were taken of 79 out of the total of 113 Space Shuttle missions, of which 65 showed some foam loss, i.e. 82%.
27 See Diane Vaughan’s book:”The Challenger Launch Decision: Risky Technology, Culture and Deviance at NASA”, The University of Chicago Press
(1996)
28 CAIB Report, page 130
29 CAIB Report, page 118.
30 CAIB Report, page 180.